Registered RAM in Xserve G5

[bunnspecial]

I spent some time on Google, but couldn't find an answer to this.

The specs for XServe G5 RAM call for ECC PC-3200 unregistered RAM. The user manual and service manual emphatically state to use unregistered RAM.

The problem I keep running into is that it seems to be difficult to find aftermarket PC-3200 RAM that is both ECC and unregistered-those features seem to go hand in hand. I have a little bit of DDR2 ECC unregistered RAM, but of course that doesn't do me any good.

In fact, I have a couple of 2gb registered ECC DIMMs that I'd like to use(my Xserve is supposed to support 2gb DIMMs), but it doesn't seem as though I can.

Most of the internet references I've found just repeat Apple's line about not using registered RAM. I'm assuming that Apple had a good reason for specifying unregistered RAM, but I also know that often times in the "real world" RAM specifications that Apple doesn't support will actually work just fine.

I obviously don't want to break anything, but also would like to upgrade the RAM in my computer.

Does anyone know if

1. Registered ECC RAM will work in the Xserve G5?

2. Will it cause damage to the computer by doing so?

 

[gavinstubbs09]

I will post a bit about ECC ram and a Late 05 PMG5.

I have 16GB (8x2GB) of ECC DDR2 ram and the G5 refused to bot with it beeping at me so I had to go back to unbuffered ram and it worked.

I have also tried ECC DDR in my Early 05 2.3 G5 and that beeped away at me too.

Sooooo I'm going to say these things hate ECC. And it won't do damage to your Mac for trying it in it.

 

[bunnspecial]

I find it interesting that ECC caused problems in your late '05 since it was actually a BTO option for those models.

In any case, ECC was actually specified for the Xserves. Mine still has the RAM in what I assume is its factory configuration, and has 8x512mb PC-3200 ECC(the box is marked 4gb RAM).

I think the key in both cases is that the RAM is unregistered.

My single 1.8 G5 currently has 6gb-it has 4x512mb and 4x1gb. The 1gb sticks(scavenged from surplus) have heat spreaders on them. I'd been told that this was indicative of registered RAM. It works fine, and doesn't show up as registered in system profiler(it's also not ECC).

I may just try the registered RAM, though, and see what happens.

 

[Surrat]

I will post a bit about ECC ram and a Late 05 PMG5.

I have 16GB (8x2GB) of ECC DDR2 ram and the G5 refused to bot with it beeping at me so I had to go back to unbuffered ram and it worked.

I have also tried ECC DDR in my Early 05 2.3 G5 and that beeped away at me too.

Sooooo I'm going to say these things hate ECC. And it won't do damage to your Mac for trying it in it.

I have 16gig ecc ram in my G5 Quad, and never had a problem with it. It shows up correctly and the ecc works. Its not buffered or registered, just ecc.

This is the exact ram thats in my quad:
http://www.memory4less.com/m4l_itemdetail.aspx?itemid=1440126174
That page lists it as 'micronet', but it isnt, all eight pieces are Micron ram.

 

[weckart]

I don't have an XServe but I own three HPservers all of which require unbuffered RAM. I can use non-EEC and in two mix and match EEC and non-EEC. Nevertheless, registered RAM is a big no-no. I made the mistake of buying some EEC RAM without checking. It will either not boot or will not be recognised. Registered RAM is plentiful and cheaper than other sorts because it is less useful. Don't be tempted.